A machine's ability to communicate with humans in a natural manner remains a difficult problem. Cognitive research on human interaction shows that a person asking a question or giving a command typically relies heavily on context and the domain knowledge of the person answering. On the other hand, machine-based queries (e.g., questions, commands, requests, and/or other types of communications) may be highly structured and are not inherently natural to the human user. Thus, human questions and machine processing of queries may be fundamentally incompatible. Yet the ability to allow a person to make natural language speech-based queries remains a desirable goal.
Much work covering multiple methods has been done in the fields of natural language processing and speech recognition. Speech recognition has steadily improved in accuracy and today is successfully used in a wide range of applications. Natural language processing has previously been applied to the parsing of speech queries. Yet, current systems are generally unable to provide a complete environment for users to make natural language speech queries and receive natural sounding responses. There remains a number of significant barriers to creation of a complete natural language speech-based query and response environment.